A group of six NIH-funded cell and developmental biologists from the University of California Berkeley, together with the UC Berkeley Molecular Imaging Center (MIC), request funds to purchase a spinning disk confocal microscope system for real-time and time-lapse imaging of dynamic cellular and developmental processes. Spinning disk confocal microscopes have emerged as unique and powerful tools for imaging dynamic cellular and developmental processes including cytoskeleton dynamics, membrane trafficking, nuclear transport, pathogen infection, and tissue morphogenesis. These instruments employ a parallel, multi-beam scanning approach that allows significantly faster image acquisition compared to standard laser scanning confocal microscopes, enabling the imaging of cellular processes that occur on a very rapid time scale. Moreover, when combined with very sensitive, electron multiplying CCD cameras, such systems have the additional advantage of acquiring images at low illumination levels, which minimizes photodamage to samples and permits extended imaging of living cells and tissues. Although access to a spinning disk microscope has become vital for the six major users on this application to accomplish the objectives of their NIH funded research, no such system is currently available for their use on the UC Berkeley campus. In addition, general demand at UC Berkeley for a fast and sensitive confocal imaging system is likely to be very high because currently available conventional laser scanning microscopes are very heavily used, which is slowing the progress of NIH- funded research. To ensure the successful operation and support of the instrument and to broaden the potential user base when the instrument is not occupied by the major users, the microscope will be incorporated into the Molecular Imaging Center (MIC), an existing microscopy facility that is jointly supported by the Department of Molecular and Cell Biology, the Cancer Research Laboratory, and the Helen Wills Neuroscience Institute. The MIC will oversee training, operation and maintenance for the instrument. This plan is will enable the instrument to support the NIH-funded research of the major users while at the same time maximizing the potential to train and support new users on the UC Berkeley campus.